Am I stupid or is my copy of the game broken? I can't fire Grenades or Rockets or anything else that is supposed to work with the RMB. I also tried changing the controll settings to space, but nothings seems to work...

Seems you have to follow all the tutorial prompts in order before it will let you do anything. I started the first game using a 360 controller and it didn't like that and I was locked out of the secondary fire as well, even after switching to mouse in the middle.

Or maybe it was a different reason, I don't know. The next game I tried starting with WASD and it all worked once I followed the prompts.

^This is sad. If you leave the opening room (which appears to be the duration of the tutorial) everything should unlock. I was told wads to move. I did. The text stayed on the screen and by the time I left the first room, no more tutorials were shown, but I was constantly told "use right click to detinate a sent out grenade" even though the game wouldn't pick any powerups up.

Googled into this post, re-started the game, got though the 7 pages of tutorial (teaching me nothing, as the game is very intuitive) and proceded to enjoy it.